Fatigue is that feeling of tiredness, exhaustion, and lack of energy. It usually comes from a combination of mental, physical and emotional influences.

Fatigue is recognised worldwide as a leading cause of accidents and incidents.

In 2009 an ATR-42 on a night cargo flight crashed in extremely poor weather conditions, including low cloud and freezing drizzle, during an ILS approach. The aircraft was written off but the crew escaped unharmed.

An aircraft flap problem, combined with the weather and a lack of aircraft control and decision making by the two crew members, were identified as the main causes.

Another significant cause was also identified. The captain was suffering from severe sleep debt due to split shifts and a lack of adequate sleep. The resulting fatigue led to severely impaired performance by the experienced captain.

The full accident report is available at www.ntsb.gov/doclib/reports/2011/AAR1102.pdf

In 2009 an ATR 42 on a freight flight was on the 17R ILS approach to Lubbock Airport in Texas at 0430 in the morning. The cloud base was 500 feet and there was freezing drizzle present.

The First Officer is the pilot flying and the Captain is the pilot monitoring. This simulation starts during the approach at nine miles and established on the approach.

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This aeroplane has only one flap indicator needle. It cannot show flap asymmetry directly like the animation does. Neither is there a warning light to show asymmetry. Flap asymmetry is identified by the flap indicator showing a position other than that selected. It is then confirmed by looking at the exterior flap position fairings.

Please click Play button to start